Question

1. rank three samples in order of increasing (a) number of particles, (b) increasing mass in grams, and (c) increasing mole amounts

sample 1: 1.0 mole of carbon
sample 2: 18 grams of carbon monoxide
sample 3: 3.0×10² formula units mgcl₂
sample 4: 5.0 l co₂ hint at stp (standard temperature and pressure): 1 mol of any gas = 22.4 l of that gas

Explanation:

Step1: Calculate moles of each sample

Sample 1: 1.0 mol of C. Sample 2: $n_{CO}=\frac{18g}{28.01g/mol}\approx0.64mol$. Sample 3: $n_{MgCl_2}=\frac{3.0\times10^{23}}{6.022\times10^{23}mol^{-1}}\approx0.5mol$. Sample 4: $n_{CO_2}=\frac{5.0L}{22.4L/mol}\approx0.22mol$.

Step2: Relate moles to number of particles and mass

Number of particles is proportional to moles. Mass $m = nM$.
(a) Increasing number of particles: Sample 4 < Sample 3 < Sample 2 < Sample 1.
(b) Mass of Sample 1: $m_{C}=1.0mol\times12.01g/mol = 12.01g$. Mass of Sample 3: $m_{MgCl_2}=0.5mol\times95.21g/mol = 47.605g$. Increasing mass: Sample 4 < Sample 1 < Sample 2 < Sample 3.
(c) Increasing mole - amounts: Sample 4 < Sample 3 < Sample 2 < Sample 1.

Answer:

(a) Sample 4, Sample 3, Sample 2, Sample 1
(b) Sample 4, Sample 1, Sample 2, Sample 3
(c) Sample 4, Sample 3, Sample 2, Sample 1